This application is to continue our Southern California Environmental Health Services Center whose main purposes are 1) to study the effects of environmental exposures on humans; 2) to determine host factors (genetic and other) influencing response to these exposures; and 3) to inform the public. To accomplish these goals we bring together an interdisciplinary team of investigators from 2 major Souther California universities: USC and UCLA. The research of our Center features interdisciplinary cornerstones: detained exposure assessment, including toxicokinetics and biomarkers; cutting edge study design, including the most powerful statistical and epidemiologic approaches; and the basic sciences, including physiology, molecular biology, genetics, chemistry and engineering. The foci of the Center cover a wide range of problems and address environmental exposures of public health importance including indoor and outdoor air pollution, pesticides, alflatoxins, radiation, passive smoking, bioaerosols and nitrites. The 5 Research Cores consist of: Respiratory Effects; Exposure Assessment; Childhood Cancer, Adult Cancer Study Design and Statistical Methodology. The 3 Facility Cores consist of: the Molecular Biology, Sample Processing and Storage Core; the Analytic Chemistry, Exposure Assessment and Aerosol Sciences Core; and the Biostatistics Core. The Center also features a separate core for Community Outreach and Education (COEP). The Center is structured to promote interdisciplinary research and linkage between the research and the COEP. Processes creating these interactions include the seminar series, pilot projects, research focus groups, workshops and retreats. The first 4 years of support for this Center have resulted in recruitment of new investigators, more investigators working on environmental health problems, doubling of funding support, more interaction between researchers from different disciplines and a greater production of research findings relevant to answering critical public health questions. The Center also developed research initiatives for the next 5 years that focus the interdisciplinary team of investigators on important environmental health problems involving genetic-environmental interactions as asthma and cancer.